Publications [LaTeX]

Books

Edited

1 - International Workshop on Hadron Physics - Effective Theories of Low-Energy QCD, Coimbra 1999
A. H. Blin, B. Hiller, M. C. Ruivo, C. A. Sousa, E. van Beveren (Eds)
American Institute of Physics Conference Proceedings 508 (2000)

2 - Proceedings of the Conference on Many Body Physics
C. Fiolhais, M. Fiolhais, C. A. de Sousa and J. N. Urbano (Eds.)
World Scientific, Singapore (1994)

Papers

International Journals

3 - Atwood machine as a tool to introduce variable mass systems
Célia A. de Sousa
Physics Education 47, 169-173 (2012)

4 - Another look at the projectile motion
Célia A. de Sousa
LAJPE 6, 31-38 (2012)

5 - Falling chains as variable mass systems: theoretical model and experimental analysis
Célia A. de Sousa, Paulo M. Gordo and Pedro Costa
Eur. J. Phys. 33, 1007-1020 (2012)

6 - Effects of entanglement and instanton suppression at ﬁnite temperature in a SU(2) EPNJL model with anomaly
M. C. Ruivo, P. Costa, C. A. de Sousa
Phys. Rev. D 86, 116007-9 (2012)

7 - Interplay between chiral and axial symmetries in a SU(2) Nambu--Jona-Lasinio Model with the Polyakov loop
M. C. Ruivo, M. C. Santos, Pedro Costa and C. A. de Sousa
Phys. Rev. D 85, 036001-10 (2012)

8 - How parameters and regularization affect the PNJL model phase diagram and thermodynamic quantities
Pedro Costa, H. Hansen, M. C. Ruivo, C. A. Sousa
Phys. Rev. D 81, 016007-13 (2010)

9 - Phase Diagram and Critical Properties within an Effective Model of QCD: The Nambu-Jona-Lasinio Model Coupled to the Polyakov Loop
Pedro Costa, Maria C. Ruivo, Célia A. de Sousa and Hubert Hansen
Symmetry (Special Issue Symmetry Breaking Phenomena) 2(3), 1338-1374 (2010)

10 - Scalar-pseudoscalar meson behavior and restoration of symmetries in SU(3) PNJL model
P. Costa, M. C. Ruivo, C. A. de Sousa, H. Hansen, W.M. Alberico
Phys. Rev. D 79, 116003-116027 (2009)

11 - Effects of the Regularization on the Restoration of Chiral and Axial Symmetries
P. Costa, M. C. Ruivo, C. A. de Sousa
Phys. Rev D 77, 096009-7 (2008)

12 - Behavior of the topological susceptibility at finite T and $mu$ and signs of restoration of chiral symmetries
M. C. Ruivo, Pedro Costa, C. A. de Sousa
European Physical Journal A 4, 766-768 (2007)

13 - Phase transitions in quark matter and behaviour of physical observables in the vicinity of the critical end point
P. Costa, C. A. de Sousa, M. C. Ruivo, Yu. L. Kalinovsky
European Physical Journal A 4, 842-844 (2007)

14 - The QCD critical end point in the SU(3) Nambu--Jona-Lasinio model
P. Costa, C. A. de Sousa, M. C. Ruivo, Yu. L. Kalinovsky
Physics Letters B 647, 431-435 (2007)

15 - Effective restoration of chiral and axial symmetries at finite temperature and density
M. C. Ruivo, P. Costa, C. A. de Sousa, Yu. L. Kalinovsky
J. Phys. G: Nucl. Part. Phys. 31, S1183 (2005)

16 - Analysis of the UA1 symmetry breaking and restoration effects on scalar-pseudoscalar meson septrum
P. Costa, M. C. Ruivo, C. A. de Sousa and Yu. L. Kalinovsky
Phys. Rev. D 71, 116002-18 (2005)

17 - Mass redistribution in variable mass systems
Célia A. de Sousa and Víctor H. Rodrigues
European Journal of Physics 25, 41-49 (2004)

18 - Effective restoration of the UA(1) symmetry with temperature and density
P. Costa, M. C. Ruivo, C. A. de Sousa, and Yu. Kalinovsky
Phys. Rev. D 70, 116013-5 (2004)

19 - Pseudoscalar Mesons in Hot and Dense Matter
P. Costa, M. C. Ruivo, Yu. Kalinovsky and C. A. de Sousa
Phys. Rev. C 70, 025204-13 (2004)

20 - Nonrigid systems: mechanical and thermodynamic aspects
Célia A. de Sousa
European Journal of Physics 23, 433-440 (2002)

21 - Pion and rho meson observables in a Nambu-Jona-Lasinio model including a tensor interaction
M. Jaminon, M. C. Ruivo and C. A. de Sousa
International Journal of Modern Physics A 17 (32), 4903-4925 (2002)

22 - La legge di conservazione dell´energia: applicazione al rotolamento con e senza strisciamento
Célia A. de Sousa and Elisa P. Pina
La Fisica nella Scuola (Tradução de Paolo Nardini) 4, 184-190 (2000)

23 - Kaons in a Hot and Flavor Asymmetric Medium
M.C. Ruivo, C. A. de Sousa and C. Providência
Nucl. Phys. A 651, 59-70 (1999)

24 - Effects of Flavor Asymmetric Media on Pion and Kaon Properties
C. A. de Sousa and M.C. Ruivo
Nucl. Phys. A 629, 552c-555c. (1998)

25 - Aspects of Mechanics and Thermodynamics in Introductory Physics: an Illustration in the Context of Friction and Rolling
Célia A. de Sousa and Elisa P. Pina
European Journal of Physics 18, 334-337 (1997)

26 - Dirac Sea Effects in a Linear sigma Model with Vector and Axial Vector Fields
C. A. de Sousa
International Journal of Modern Physics A 10, 963-976 (1995)

27 - Medium Effects on Meson Properties
M. C. Ruivo, C. A. Sousa, B. Hiller and A. H. Blin
Nucl. Phys. A 575, 460-476 (1994)

28 - Semi-Classical Description of Dynamical Properties of Mesonic Excitations in the Nambu-Jona-Lasinio Model
J. da Providência, M. C. Ruivo and C. A. de Sousa
Europhys. Lett. 21, 521-526 (1993)

29 - The Energy-Weighted Sum Rule in the Nambu-Jona-Lasinio Model and the Properties of Mesons Pi, pi'
C. A. de Sousa
Modern Physics Letters A 7, 207-213 (1992)

30 - Meson Resonances in a Generalized Nambu and Jona-Lasinio Model
C. A. de Sousa
Zeitschrift fur Physik C - Particles and Fields 49, 619-626 (1991)

31 - Time Dependent Hartree-Fock Approach to the Bosonic Excitations of the Nambu-Jona-Lasinio Model in the Continuum
J. da Providência and C. A. de Sousa
Physics Letters B 237, 147-152 (1990)

32 - Order Parameters and Properties of the sigma-pi sector in the Nambu-Jona-Lasinio Model
C. A. de Sousa
Zeitschrift fur Physik C - Particles and Fields 43, 503-508 (1989)

33 - Dispersion Relation of the Pion in the Nambu-Jona- Lasinio Model
J. da Providência, M. C. Ruivo and C. A. de Sousa
Phys. Rev. D 38, 2646-2647 (1988)

34 - Time Dependent Hartree-Fock and the Excitations of the Dirac Sea
J. da Providência, M. C. Ruivo and C. A. de Sousa
Fizica 19, 8-12 (1987)

35 - Time Dependent Hartree-Fock Formalism and the Excitations of the Dirac Sea in the Nambu-Jona- Lasinio Model
J. da Providência, M. C. Ruivo and C. A. Sousa
Phys. Rev. D 36, 1882-2647 (1987)

36 - Investigation of Pion-Like Collective Excitations in Neutron Matter through Boson Expansion Techniques
C. A. de Sousa
Progress of Theoretical Physics 74, 725-735 (1985)

37 - Anharmonic Effects and Pre-Critical Behaviour in Pion Condensation
M. C. Ruivo, C. A. Sousa and L. P. Brito
Prog. Theor. Phys. 69, 542-556 (1983)

38 - Classical Analogy of the Concept of Collective Variables
L. P. Brito and C. A. de Sousa
Journal of Physics A: Math. and Gen. 14, 2239-2249 (1981)

39 - Time Dependent Generator Coordinate Method and the N-N Interaction
L. P. Brito and C. A. de Sousa
Portugaliae Physica 12, 1-7 (1981)

40 - Comparison of Convergence Rates of Boson Expansions,
M. H. Caldeira and C. A. de Sousa
Fizika (Zagreb) 11, 43-50 (1979)

41 - Collective Hamiltonian in Adiabatic Approximation
A. Alves, L.P. Brito, M. H. Caldeira, J. M. Domingos, P. Martins, H. Pascoal, J. da Providência, M. C. Ruivo, E. M. Silva, C. A. de Sousa and J. N. Urbano
Prog. Theor. Phys. 58, 223-230 (1977)

42 - Note on the Applicability of the Peierls-Yoocoz Method
A. Alves, L.P. Brito, M. H. Caldeira, J. M. Domingos, P. Martins, H. Pascoal, J. da Providência, M. C. Ruivo, E. M. Silva, C. A. de Sousa and J. N. Urbano
Nucl. Phys. A 284, 420-424 (1977)

43 - The Hartree-Fock and the Generator Coordinate Method in Field Theory: The Polaron Problem
J. da Providência , M. C. Ruivo and C. A. de Sousa
Ann. of Phys., N. Y. 91, 366-374 (1975)

44 - Description of Anharmonicities in a Solvable Model by the Generator Coordinate Method
M. H. Caldeira and C. A. de Sousa
Fizika (Zagreb) 7 (2), 19-31 (1975)

Portuguese Journals

45 - Sobre Algumas Questões de Mecânica do 10º Ano
João Tremoço e Célia A. de Sousa
Gazeta de Física vol 23, fasc. 4, 10 (2000)

46 - A Lei de Conservação da Energia: Aplicação ao Rolamento com e sem Deslizamento
Célia A. de Sousa e Elisa P. Pina
Gazeta de Física 22 fasc 2, 10 (1999)

Proceedings

International Conferences

47 - Restoration of axial symmetry and its possible relations with restoration of chiral symmetry and deconfinement at finite temperature
M. C. Ruivo, P. Costa and C. A. de Sousa
Acta Physica Polonica B Proceedings Supplement 6 no.3, 917-922 (2013)

48 - Some properties of two Nambu-Jona-Lasinio -type models with inputs from lattice QCD
P. Costa, C. A. de Sousa, M. C. Ruivo, O. Oliveira, P. J. Silva, and H. Hansen
Acta Physica Polonica B Proceedings Supplement 5 no.4, 1083-1088 (2012)

49 - The QCD Critical End Point in the Context of the PolyakovNambuJona-Lasinio Model
P. Costa, M.C. Ruivo, C. A. de Sousa, and H. Hansen
Acta Physica Polonica B Proceedings Supplement 5 no. 2, 523-528 (2012)

50 - Phase Diagram and Critical Properties in the PNJL Model
Célia A. de Sousa, P. Costa, M. C. Ruivo and H. Hansen
Procceedings of the International Conference on Quark Confinement IX, Madrid 2010, AIP Conf. Proc (Eds. F. J. Llanes-Estrada and J. R. Peláez) 1343, 592 (2011)

51 - Scalar-pseudoscalar meson spectrum in SU(3) PNJL model
Pedro Costa, M.C. Ruivo, C. A. de Sousa, H. Hansen and W.M. Alberico
PoS(Confinement8) 086, Proceedings of the Quark Confinement and the Hadron Spectrum VIII: 8th Conference on Quark Confinement and the Hadron Spectrum, Mainz, Germany, 1-6 Sep 2008. (2008)

52 - Behavior of the topological susceptibility at finite T and $mu$ and signs of restoration of chiral symmetries
M. C. Ruivo, P. Costa, C. A. de Sousa
IVth International Conference on Quarks and Nuclear Physics (QNP06), A. Dobado, F. J. Llanes-Estrada and V. Vento (Eds.), Springer-Verlag, Berlin Heidelberg, 465-467 (2007)

53 - Phase transitions in quark matter and behaviour of physical observables in the vicinity of the critical end point
P. Costa, C. A. de Sousa, M. C. Ruivo, Yu. L. Kalinovsky
IVth International Conference on Quarks and Nuclear Physics (QNP06), A. Dobado, F. J. Llanes-Estrada and V. Vento (Eds.), Springer-Verlag, Berlin Heidelberg, 553-555 (2007)

54 - Phase transitions and behavior of kaons in hot and dense matter,
C. A. de Sousa, P. Costa, M. C. Ruivo, Yu. L. Kalinovsky
Proceedings of the Quark Confinement and the Hadron Spectrum VI, Eds. N. Brambilla et al., AIP Conf. Proc., New York 756, 348 (2005)

55 - Effects of the restoration of UA(1) symmetry on pseudoscalar meson observable
M. C. Ruivo, Pedro Costa, C. A. de Sousa, Yu. L. Kalinovsky
PoS(HEP2005), 109 (2005)

56 - Is the UA(1) symmetry restored at finite temperature or density?
P. Costa, M. C. Ruivo, C. A. de Sousa, and Yu. Kalinovsky
Proceedings of the Quark Confinement and the Hadron Spectrum VI, Eds. N. Brambilla et al., AIP Conf. Proc. New York 756, 351 (2005)

57 - The restoration of the UA(1) symmetry and the meson spectrum in hot or dense matter
P. Costa, M. C. Ruivo, C. A. de Sousa, and Yu. L. Kalinovsky
Proceedings of Hadronic Physics: Joint Meeting Heidelberg-Liège-Paris-Rostock; HLPR 2004, Eds. J. P. Lansberg et al., Aip Conf. Proc., New York 775, 173 (2005)

58 - Pion and rho meson observables in a Nambu-Jona-Lasinio model including a tensor interaction
M. Jaminon, M. C. Ruivo and C. A. de Sousa
Workshop on Hadron Physics, Ed. B. Hiller, Coimbra (2002)

59 - Kaon Properties in a Hot and Dense Medium
M. C. Ruivo, C. A. de Sousa and C. Providência
Proceedings of International Workshop on Understanding Deconfinement in QCD, ECT, Trento, 1999, D. Blaschke, F. Karsch and C. Roberts, (Eds.) World Scientific, Singapore, 268-271 (2000)

60 - Effective Kaon Mass in Symmetric Nuclear Matter
M.C. Ruivo and C. A. de Sousa
Proceedings of the XIV International Conference on Particles and Nuclei, PANIC 96, Williamsburg, Eds. C.E. Carlson and J.J. Domingo, World Scientific, Singapore, 605-606 (1997)

61 - Medium effects on pi-pi scattering and in the rho-pi-pi decay
M.C. Ruivo, C. A. de Sousa, A.H. Blin and B. Hiller
Proceedings of the Conference on Many Body Physics, ed. C. Fiolhais et al, World Scientific, Singapore, 179-182 (1994)

62 - Anharmonic effects on pionic modes
M. C. Ruivo and C. A. de Sousa
Proceedings of the 1st Workshop on Perspectives in Nuclear Physics at Intermediate Energies, Trieste, Eds. S. Boffi, C. Ciofi degli Atti and M.M. Giannini, World Scientific, Singapore, 527-529 (1984)

Communications

Invited

63 - Restoration of axial symmetry and possible relations with restoration of axial symmetry and deconfinement at finite temperature
M. C. Ruivo, P. Costa and C. A. de Sousa
International Workshop on Excited QCD 2013, Bjelasnica Mountain, Bosnia, February (2013)

64 - Pseudoscalar mesons in asymmetric media
M. C. Ruivo, P. Costa and C. A. de Sousa
International Workshop on Quark Matter in Astro and Particle Physics, University of Rostock, Germany, 2001. (2001)

65 - Kaon Properties in a Hot and Dense Medium
M.C. Ruivo, C. A. de Sousa and C. Providência
International Workshop on Understanding Deconfinement in QCD, Trento, Itália, Março (1999)

66 - The Nambu-Jona-Lasinio model in the TDHF formalism
J. da Providência. M. C. Ruivo and C. A. de Sousa
I Encontro Luso-Soviético de Física Nuclear Lisboa, Novembro (1990)

67 - Time-Dependent Hartree-Fock and the Excitations of the Dirac Sea
J. da Providência, M. C. Ruivo and C. A. de Sousa
Workshop on Meson Degrees of Freedom in Hadrons Bled/Ljubljana, Jugoslávia 1987 (1987)

Oral

68 - Restoration of axial symmetry and its possible relations with restoration of chiral symmetry and deconfinement at finite temperature
M. C. Ruivo, P. Costa and C. A. de Sousa
Talk given at the Exited QCD 2013, 3-9 February, Bjelasnica, Sarajevo - Bosnia (2013)

69 - Modeling Chiral and Deconfinement Transitions in the Context of the Polyakov--Nambu--Jona-Lasinio Model
P. Costa, C. A. de Sousa, M. C. Ruivo, H. Hansen,
Talk given at the SQM 2011 Strangeness in Quark Matter, 18-24 September, Krakow, Poland (2011)

70 - Phase Diagram and Critical Properties in the PNJL Model
Célia A. de Sousa, P. Costa, M. C. Ruivo and H. Hansen
Talk given at the International Conference on Quark Confinement IX, Madrid, 30/08 to 3/09 (2010)

71 - How the Polyakov loop and regularization procedures affect the behavior of strange quark matter and restoration of symmetries at finite T
M. C. Ruivo, P. Costa, C. A. de Sousa, H. Hansen and W. Alberico
Talk given at the XII International Conference on Hadron Spectroscopy, 29 November - 4 December, Tallahassee, Florida, USA (2009)

72 - Exploring the role of model parameters and regularization procedures in the thermodynamics of the PNJL model
M. C. Ruivo, P. Costa, H. Hansen and C. A. de Sousa
Talk given at the XII International Conference on Hadron Spectroscopy, 29 November - 4 December, Tallahassee, Florida, USA (2009)

73 - Scalar-pseudoscalar meson spectrum in SU(3) PNJL model
Pedro Costa. M. C. Ruivo, C. A. de Sousa, H. Hansen and W.M. Alberico
Quark Confinement and the Hadron Spectrum VIII: 8th Conference on Quark Confinement and the Hadron Spectrum, Mainz, Germany, 1-6 September (2008)

74 - Phase structure, critical points and susceptibilities in Nambu-Jona-Lasinio type models
C. A. de Sousa, Pedro Costa, and M. C. Ruivo
Talk given at 12th International Conference on Hadron Spectroscopy (Hadron 07), Frascati, Italy, 8-13 October (2007)

75 - Behavior of the topological susceptibility at finite T and $mu$ and signs of restoration of chiral symmetries
M. C. Ruivo, Pedro Costa, C. A. de Sousa
IVth International Conference on Quarks and Nuclear Physics (QNP06), Madrid, Spain (2006)

76 - Phase transitions in quark matter and behaviour of physical observables in the vicinity of the critical end point
Pedro Costa, C. A. de Sousa, M. C. Ruivo, Yu. L. Kalinovsky
IVth International Conference on Quarks and Nuclear Physics (QNP06), Madrid, Spain (2006)

77 - Effects of the restoration of UA(1) symmetry on meson observables
M. C. Ruivo, P. Costa, C. A. de Sousa and Yu. L. Kalinovsky
International Europhysics Conference on High Energy Physics, Lisbon Portugal, 21.27 July (2005)

78 - Phase transitions and behavior of kaons in hot and dense matter
C. A. de Sousa, P. Costa, M. C. Ruivo, Yu. L. Kalinovsky
Quark Confinement and the Hadron Spectrum VI 2004, Villasimios, Cagliari Italy (2004)

79 - Effective restoration of chiral and axial symmetries at finite temperature and density
M. C. Ruivo, P. Costa, C. A. de Sousa, Yu. L. Kalinovsky
VIII International Conference on Strangeness in Quark Matter, Cape Town, South Africa (2004)

80 - Is the UA(1) symmetry restored at finite temperature or density?
P. Costa, M. C. Ruivo, C. A. de Sousa, and Yu. Kalinovsky
Quark Confinement and the Hadron Spectrum VI 2004, Villasimios, Cagliari Italy (2004)

81 - The restoration of the UA(1) symmetry and the meson spectrum in hot or dense matter
P. Costa, M. C. Ruivo, C. A. de Sousa, and Yu. L. Kalinovsky
Three Days of Hadronic Physics, Sol Cress, Spa - Belgium (2004)

82 - J/psi dissociation at finite temperature/density
Yu. L. Kalinovsky, P. Costa, M. C. Ruivo, C. A. de Sousa, and J. Cugnon
Three Days of Hadronic Physics´, Sol Cress, Spa - Belgium, 16 18 December (2004)

83 - Effects of Flavor Asymmetric Media on Pion and Kaon Properties
C. A. de Sousa and M.C. Ruivo
Quark Lepton Nuclear Physics International Conference, Osaka, Japão, Maio (1997)

84 - Many-Body Approach to a NJL type model
M.C. Ruivo and C. A. Sousa
New Problems in the the General Theory of Particles and Fields, Paris, July (1994)

85 - Medium effects on pi-pi scattering and on the rho-pi-pi decay
M.C. Ruivo, C. A. de Sousa, A.H. Blin and B. Hiller
International Conference on Many Body Physics, Coimbra, Portugal, September (1993)

86 - Anharmonic Effects in Pionic Modes
M. C. Ruivo and C. A. de Sousa
Workshop on Perspectives in Nuclear Physics at Intermediate Energies Trieste, Italy, October (1983)

87 - Efeitos Anarmónicos e Fenómenos Pré-Críticos na Condensação de Piões
M. C. Ruivo C. A. de Sousa and L. P. Brito
Conferência Nacional de Física 82, Coimbra (1982)

Poster

88 - Propriedades de Piões a Temperatura e Densidades Finitas
P. Costa, M.C. Ruivo e C. A. de Sousa,
Física 2000, Figueira da Foz Portugal (2000)

89 - Kaons at finite baryonic density and temperature
M. C. Ruivo and C. A. de Sousa
Baryons 95, Santa Fe, USA (1995)

90 - The Energy Weighted Sum Rule in NJL type models
M. C. Ruivo and C. A. de Sousa
International Congress of Mathematical Physics, Paris (1994)

91 - Mesonic Modes in the Continuum of the Nambu-Jona-Lasinio Model: Masses and Decays
M. C. Ruivo and C. A. de Sousa
PANIC XII - International Conference on Particles and Nuclei, Massachusets Institute of Technology, Cambridge MA, USA. (1990)

Thesis

92 - O Vácuo e as Excitações Mesónicas em Modelos do Tipo de Nambu-Jona-Lasinio
Célia Almeida de Sousa
Phd thesis, Universidade de Coimbra (1990)

Célia Almeida de Sousa